The proposed research program is concerned with the development of materials and components leading to the design of new miniature fiberscopes for visualization, biopsy, and microsurgery. It builds on existing unique technological developments in the Fiber-Optics Research Laboratory of Northwestern University such as the preparation of microlenses (0.5 millimeter in diameter) and improved methods of fabrication of miniature rigid and flexible imaging multifibers made of glass and plastics. The design of specific instruments will be conducted in close cooperation with medical researchers from the earliest concepts in order to appropriately direct the relevant developments in materials and components. The choice of instruments, some of which have already been identified and the construction of their prototypes already completed, will be diverse to assure the widest spectrum of functional design, thus allowing for effective extensions into other designs. A close cooperation with industry has also been established to provide for a speedy and effective transfer of the proposed developments. A limited quantity of newly developed materials and components will be made available to other instrument designers. In addition to the conventional methods of publications, results of work in the development of specific prototype instruments and their clinical applications will be disseminated through special workshops and seminars. It is the intention that the proposed research program serve engineering and clinical researchers in the development of optical instrumentation in medicine.